不同饲料对海月水母生长性能的影响

研究了5种饲料对海月水母Aurelia aurita(伞体直径为2.50 cm±0.10 cm)生长性能的影响.实验共分5组,每组设3个平行,分别投喂卤虫无节幼体、冰冻卤虫、冷冻干燥卤虫、国产微粒饲料和国外微粒饲料,依照投喂饲料的不同,各组分别记为G鲜活、G冰冻、G干燥、G国产、G国外组,实验共进行30 d.结果表明:饲养30 d后,5组海月水母伞体的平均直径依次为(5.01±0.10)、(4.78±0.20)、(4.62±0.11)、(4.23±0.05)、(4.42±0.06)cm,卤虫无节幼体组生长性能最好,水母伞体直径显著高于其他各组(P<0.05),冰冻卤虫和冷冻干燥卤虫组次之,国产微粒饲料组生长性能最差;国产微粒饲料组的成活率为95%,其余各组成活率均为100%;卤虫无节幼体组的收缩频率平均为1次/s,显著高于其他4组(P<0.05),其余4组之间差异均不显著(P>0.05),收缩频率平均为0.5～0.66 次/s;冰冻卤虫组的三态氮含量均显著高于其他各组(P<0.05),国内微粒饲料组的三态氮含量次之,也显著高于其他3组(P<0.05).本实验结果表明,卤虫无节幼体是海月水母较理想的饵料,冰冻卤虫和冷冻干燥卤虫次之.国产微粒饲料因为在营养组成、水中稳定性和悬浮性方面较差,饲养海月水母的效果也较差.

The influence of different diets on growth performance in moon jellyfish Aurelia aurita

Moon jellyfish Amelia aurita with initial umbrella diameter of (2.50 ± 0.10)cm were fed nauplii of Ar-temia, frozen Atemia, freeze dried Atemia, Chinese microdiet and microdiet abroad for one month to evaluate the influence of the diets above on growth performance in the moon jellyfish. The moon jellyfish fed the Chinese micro-diet had survival rate of 95% , whereas the moon jellyfish fed the other diets had survival rate of 100%. The moon jellyfish fed the nauplii of Anemia showed the best growth performance, the umbrella diameter (5.01 cm ±0. 10 cm) being significant higher than the animals fed other diets(P <0.05) .followed by the moon jellyfish fed the fro-zen Atemia (4.78 cm ±0.20 cm in umbrella diameter) or freeze dried Atemia (4.62 cm ±0.11 cm in umbrella diameter). The least growth was observed in the moon jellyfish fed the Chinese microdiet (4.42 cm ±0.06 cm in umbrella diameter). The highest constraction frequency (1/second) was found in the moon jellyfish fed the nauplii of Artemia, significantly higher than those in the other groups (0.5 -0.66/second) (P < 0.05) without signifi-cant difference. The water quality of the frozen Atemia group was the worst, the average concentration of TNH_3 -N, NO_2~- -N and NO_3~- -N being significantly higher than those in the other groups(P < 0.05) , followed by the microdiet group, significantly higher than those in the other groups ( P < 0. 05 ) , indicating that nauplii were the best food for moon jellyfish. The frozen Atemia and freeze dried Atemia were also suggested to be used as food for moon jellyfish. The Chinese microdiet was not considered to be suitable for moon jellyfish due to its poor nutrition, low water stability and suspension.